React Native Fingerprint Scanner

React Native Fingerprint Scanner is a React Native library for authenticating users with Fingerprint (TouchID).

iOS Version

The usage of the TouchID is based on a framework, named Local Authentication.

It provides a Default View that prompts the user to place a finger to the iPhone’s button for scanning.

Android Version

Using an expandable Android Fingerprint API library, which combines Samsung and MeiZu's official Fingerprint API.

Samsung and MeiZu's Fingerprint SDK supports most devices which system versions less than Android 6.0.

Table of Contents

• Installation
• Example
• API
• License

Installation

$ npm install react-native-fingerprint-scanner --save

Automatic Configuration

$ react-native link react-native-fingerprint-scanner

Manual Configuration

iOS

1. In XCode, in the project navigator, right click Libraries ➜ Add Files to [your project's name]
2. Go to node_modules ➜ react-native-fingerprint-scanner and add ReactNativeFingerprintScanner.xcodeproj
3. In XCode, in the project navigator, select your project. Add libReactNativeFingerprintScanner.a to your project's Build Phases ➜ Link Binary With Libraries
4. Run your project (Cmd+R)

Android

1. Open up android/app/src/main/java/[...]/MainActivity.java

• Add import com.hieuvp.fingerprint.ReactNativeFingerprintScannerPackage; to the imports at the top of the file
• Add new ReactNativeFingerprintScannerPackage() to the list returned by the getPackages() method

2. Append the following lines to android/settings.gradle:

   include ':react-native-fingerprint-scanner'
   project(':react-native-fingerprint-scanner').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-fingerprint-scanner/android')
   

3. Insert the following lines inside the dependencies block in android/app/build.gradle:

   compile project(':react-native-fingerprint-scanner')
   

Extra Configuration

1. Make sure the following versions are all correct in android/app/build.gradle

   android {
       compileSdkVersion 25
       buildToolsVersion "25.0.3"
   ...
       defaultConfig {
         targetSdkVersion 25
   

2. Add necessary rules to android/app/proguard-rules.pro

   # MeiZu Fingerprint
   
   -keep class com.fingerprints.service.** { *; }
   
   # Samsung Fingerprint
   
   -keep class com.samsung.android.sdk.** { *; }
   

Example

Example Source Code

iOS Implementation

import React, { Component, PropTypes } from 'react';
import { AlertIOS } from 'react-native';
import FingerprintScanner from 'react-native-fingerprint-scanner';

class FingerprintPopup extends Component {

  componentDidMount() {
    FingerprintScanner
      .authenticate({ description: 'Scan your fingerprint on the device scanner to continue' })
      .then(() => {
        this.props.handlePopupDismissed();
        AlertIOS.alert('Authenticated successfully');
      })
      .catch((error) => {
        this.props.handlePopupDismissed();
        AlertIOS.alert(error.message);
      });
  }

  render() {
    return false;
  }
}

FingerprintPopup.propTypes = {
  handlePopupDismissed: PropTypes.func.isRequired,
};

export default FingerprintPopup;

Android Implementation

import React, { Component, PropTypes } from 'react';
import {
  Alert,
  Image,
  Text,
  TouchableOpacity,
  View,
  ViewPropTypes
} from 'react-native';
import FingerprintScanner from 'react-native-fingerprint-scanner';

import ShakingText from './ShakingText.component';
import styles from './FingerprintPopup.component.styles';

class FingerprintPopup extends Component {

  constructor(props) {
    super(props);
    this.state = { errorMessage: undefined };
  }

  componentDidMount() {
    FingerprintScanner
      .authenticate({ onAttempt: this.handleAuthenticationAttempted })
      .then(() => {
        this.props.handlePopupDismissed();
        Alert.alert('Fingerprint Authentication', 'Authenticated successfully');
      })
      .catch((error) => {
        this.setState({ errorMessage: error.message });
        this.description.shake();
      });
  }

  componentWillUnmount() {
    FingerprintScanner.release();
  }

  handleAuthenticationAttempted = (error) => {
    this.setState({ errorMessage: error.message });
    this.description.shake();
  };

  render() {
    const { errorMessage } = this.state;
    const { style, handlePopupDismissed } = this.props;

    return (
      <View style={styles.container}>
        <View style={[styles.contentContainer, style]}>

          <Image
            style={styles.logo}
            source={require('./assets/finger_print.png')}
          />

          <Text style={styles.heading}>
            Fingerprint{'\n'}Authentication
          </Text>
          <ShakingText
            ref={(instance) => { this.description = instance; }}
            style={styles.description(!!errorMessage)}>
            {errorMessage || 'Scan your fingerprint on the\ndevice scanner to continue'}
          </ShakingText>

          <TouchableOpacity
            style={styles.buttonContainer}
            onPress={handlePopupDismissed}
          >
            <Text style={styles.buttonText}>
              BACK TO MAIN
            </Text>
          </TouchableOpacity>

        </View>
      </View>
    );
  }
}

FingerprintPopup.propTypes = {
  style: ViewPropTypes.style,
  handlePopupDismissed: PropTypes.func.isRequired,
};

export default FingerprintPopup;

API

isSensorAvailable(): (Android, iOS)

Checks if Fingerprint Scanner is able to be used by now.

• Returns a Promise

componentDidMount() {
  FingerprintScanner
    .isSensorAvailable()
    .catch(error => this.setState({ errorMessage: error.message }));
}

authenticate({ description, fallbackEnabled }): (iOS)

Starts Fingerprint authentication on iOS.

• Returns a Promise
• description: String - the string to explain the request for user authentication.
• fallbackEnabled: Boolean - default to true, whether to display fallback button (e.g. Enter Password).

componentDidMount() {
  FingerprintScanner
    .authenticate({ description: 'Scan your fingerprint on the device scanner to continue' })
    .then(() => {
      this.props.handlePopupDismissed();
      AlertIOS.alert('Authenticated successfully');
    })
    .catch((error) => {
      this.props.handlePopupDismissed();
      AlertIOS.alert(error.message);
    });
}

authenticate({ onAttempt }): (Android)

Starts Fingerprint authentication on Android.

• Returns a Promise
• onAttempt: Function - a callback function when users are trying to scan their fingerprint but failed.

componentDidMount() {
  FingerprintScanner
    .authenticate({ onAttempt: this.handleAuthenticationAttempted })
    .then(() => {
      this.props.handlePopupDismissed();
      Alert.alert('Fingerprint Authentication', 'Authenticated successfully');
    })
    .catch((error) => {
      this.setState({ errorMessage: error.message });
      this.description.shake();
    });
}

release(): (Android)

Stops fingerprint scanner listener and optimizes memory.

• Returns a Void

componentWillUnmount() {
  FingerprintScanner.release();
}

Errors

Name	Message
AuthenticationNotMatch	No match
AuthenticationFailed	Authentication was not successful because the user failed to provide valid credentials
UserCancel	Authentication was canceled by the user - e.g. the user tapped Cancel in the dialog
UserFallback	Authentication was canceled because the user tapped the fallback button (Enter Password)
SystemCancel	Authentication was canceled by system - e.g. if another application came to foreground while the authentication dialog was up
PasscodeNotSet	Authentication could not start because the passcode is not set on the device
FingerprintScannerNotAvailable	Authentication could not start because Fingerprint Scanner is not available on the device
FingerprintScannerNotEnrolled	Authentication could not start because Fingerprint Scanner has no enrolled fingers
FingerprintScannerUnknownError	Could not authenticate for an unknown reason
FingerprintScannerNotSupported	Device does not support Fingerprint Scanner

License

MIT